Unconventional plays like the Wolfberry, the Wolfbone and the Horizontal Wolfcamp are getting the lion’s share of attention.

Technological advances in horizontal drilling and hydraulic fracturing that result in high initial production volumes have operators flocking to acreage in the Midland and Delaware basins.

But the conventional wells that launched the Permian Basin oil industry over 90 years ago, when cable tool rigs pounded holes in the ground until oil gushed, still have a place in today’s industry.

Unconventional resource development may be displacing conventional development but “There’s still an appetite for conventional resources,” said Benjamin Shattuck, upstream analyst with Houston’s Wood McKenzie. He was in Midland to give a technical presentation at the West Texas Geological Society’s annual Fall Symposium.

Even as operators increasingly embrace horizontal drilling, the company hasn’t noticed a significant drop in the conventional rig count, he said.

He told Symposium attendees that the most-asked question he hears is ‘How long will this last?”

Shattuck answered that his company sees the ability for strong oil and gas activity to continue for another 35 years, as sustainable production from unconventional resource plays has extended production into the mid-2030s.

Unconventional plays are driving the nation’s production growth and hydrocarbon prices are bringing development back to the oil patch, he said. Still, he said operators as a whole are concerned about prices.

Operators were cautious at first, but once rates of return began rising, they began looking for opportunities, he said.

The Permian Basin’s geology provides risk but also reward, he said. The deep benches of the Wolfcamp are attracting operators and production rates continue to outperform other formations.

“There’s a lot of upside from the geology of the Permian Basin,” said Shattuck, listing the Wolfcamp “A,” “B” and “C” benches and the Cline formations.

Multi-bench development is complex, he cautioned, and the multiple benches in the Permian Basin “are among the most challenging in the Lower 48.”

The Wolfcamp remains a statistical pay that doesn’t guarantee economic wells, he said. But operators are doing a good job of driving down costs and making more drilling projects economic, he said.

The horizontal Wolfcamp is a world-class play with upside potential throughout the stratigraphic column, Shattuck told his audience. Over $115 billion remains to be invested in the Wolfcamp and $825 billion worth of reserves remains in place, he said.

The Permian Basin is known for its “stacked” formations, with operators saying the area holds 14 producing formations. Other formations will make economic plays for some operators, Shattuck said. “We won’t see any one overtake the Wolfcamp.”